Microwave Traps and Atom Interferometry with AC Zeeman Potentials

College Of William And Mary, Williamsburg VA

Investigators

Abstract

This project will develop and characterize atom interferometers based on ultracold trapped atoms on an atom chip. Atom interferometers are the most sensitive force measuring devices ever constructed and are well suited for precision measurements and detection of electric and magnetic fields, gravity, and inertial forces, such as accelerations and rotations. Applications of atom interferometers include inertial navigation in a GPS-denied environment, remote sensing of underground structures, measuring atom-surface forces, and searching for deviations of the gravitational force from the inverse square law. While most atom interferometers operate with freely propagating atoms, one of the main scientific goals of this project is to develop and evaluate atom interferometers based on trapped atoms. Furthermore, the project will control these atoms using AC Zeeman potentials, a novel and little explored quantum control mechanism for applying forces on atoms using microwave fields generated in the vicinity of an atom chip. Graduate and undergraduate student researchers will be trained in atom interferometry, ultracold atom technologies, microwave engineering, and micro-fabrication techniques, as well as in the broadly enabling sciences of atomic and optical physics. More specifically, this project will construct ultracold trapped atom interferometers that are capable of long phase integration times with well localized, positionable atomic packets. These trapped atom interferometers will be spin-dependent so that the two arms of the interferometer have atoms in different quantum spin states. The spin-dependence will enable the interferometer to use atoms in many different spatial states so that it can employ ultracold thermal atoms or degenerate fermions, which are expected to suppress atom-atom interactions. The project will use AC Zeeman potentials generated by microwave near-fields from an atom chip to implement the spin-dependent forces and traps for the interferometer. Notably, the project will design and micro-fabricate a microwave atom chip for efficient generation of AC Zeeman potentials. An important objective of this project is to develop and characterize AC Zeeman traps and potentials, and thus evaluate them for inclusion in the toolbox of ultracold atomic physics techniques. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.